342 Bulletin Vanderbilt Marine Miiseum, Vol. VII 



Text figure 21, — Sepia rouxii d'Orbigny, ventral view of gladius, X 1. 



distance (about 6 millimeters in the present specimen) behind 

 the mantle edge and anteriorly the fins are narrowed, gradually 

 widening, being widest on the posterior two-thirds of their length, 

 where they attain a width of 10 to 12 millimeters in the present 

 specimen ; posteriorly the margin of each fin is widely rounded, 

 the two being very narrowly separated posteriorly. 



The head is of moderate size, wider than thick, flattish dor- 

 sally, somewhat convex laterally and with a distinct median de- 

 pression ventrally into which the dorsal surface of the siphon 

 fits. The eye is lateral, large, with a prominent pupil. 



The outer buccal membrane is well developed with its distal 

 margin produced into seven points : one point extends between the 

 two dorsal arms, one point each between the dorsal and upper 

 lateral arms, one point each between the margins of the lower 

 lateral and ventral arms, and the seventh point occurs between 

 the ventral pair of arms. The exposed surface of the outer buccal 

 membrane is smooth, except for marginal plaitings or ribbing, 

 apparently due to the constricted condition of the muscles in the 

 dead specimen. The inner buccal membrane is very muscular and 

 closely surrounds the beak. The exposed inner surface of the inner 



